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Why will a new system make the trains run better? It could also make it run worse, if they don’t cover all the current cases.

I’ve ridden Muni in SF for years, drivers control most of the decision making.

There’s a handful of single track tunnels/sensors/necessary software-based coordination, but as another commenter pointed out, the doors cause more issues than signal problems.




  I’ve ridden Muni in SF for years, drivers control most of the decision making.
All of the tunnels are under automatic operation, and the majority of the switches (street or tunnel) are computer controlled.

  the doors cause more issues than signal problems.
While doors are a real common failure/abuse point, I'd want to see some actual numbers on that. Train control failure may not always be self-evident to a rider, especially if the remedy is to run things manually (such that things aren't ever stopped completely).

Historically the cab signaling system would glitch in wet or damp weather. Transponders for the switches had a near 100% failure rate. Trains chewed up the inductive loops, forcing emergency braking. That was common enough that they had to dial back the emergency deceleration. Twenty years on they've mostly worked out the kinks but it hasn't always been that way.




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